Re: miniuart

John Adair wrote:

If you are connecting to a PC serial port you need a RS232 transceiver chip
between the signals and the FPGA as the voltage levels are not directly
compatible with FPGAs or most other logic chips for that matter. Many
development boards have driver chips on board or like us have a add-on
module for this if you are using one of these. If you have a development
board then the boards with the "fixed" solution will predetermine FPGA pins.
Our approach you assign the pins of the header that your are actually using.

Yes. And once you have that wired up, you should configure the FPGA
without the uart, but just sending the signal from the receive data pin
(from the transceiver) out the send data pin (through the transceiver
to the computer).

In your terminal program, this should mean anything you type is
returned to you either once (vs not at all when the cable is
disconnected) or twice (vs only once with the cable disconnected). The
difference depends on if your terminal program is running in full or
half duplex mode, or if it's hyperterminal if you have the echo local
characters box checked in the window that results from the ascii setup
button of the properties dialog.

Once you've verified the electrical part that way, you can try working
on using the uart core itself.

.

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